Background Early aggressive parenteral nutrition (APN), consisting of high protein (2.5–3.5 g/kg/day) and high lipid (2 g/kg/day) administration from birth onwards, has proven to be safe in very-low-birthweight-preterm (VLBWP) infants.

However, Bonsante F et al.¹ hypothesised that APN administration induces an anabolic state in the cell promoting potassium and phosphorus intake, decreasing their plasma concentration, which leads to an increase in plasma calcium levels.

Purpose To report the prevalence of potassium, phosphorus and calcium imbalance during the first weeks of life in a population of VLBWP infants receiving APN from day 1.

Material and methods Retrospective, observational study conducted at a third-level childrens’ hospital from January to December 2016, including preterm infants (<33 weeks’ gestational age, weight <1500 g), who received parenteral nutrition (PN) and were hospitalised in the intensive care unit within the first 24 hours of life.

Gestational age, birthweight, daily parenteral intake composition and blood concentrations of potassium, phosphate and calcium during the administration of PN were collected from the electronic health record Centricity Critical Care^®.

The main data evaluated were the mean potassium, phosphorus and calcium concentrations in plasma during treatment with PN.

Results The study included a total of 116 VLBWP infants, average 29±2.7 weeks’ gestational age, main weight 1102±321 g.

The mean duration of PN administration was 7.7 (1–68) days, with an average amino-acid and lipid intake of 2.82±0. 79 g/kg/day and 1.81±0. 68 g/kg/day, respectively.

Hypokalaemia (K<3 mmol/L) occurred in 108 (93%) infants, hypophosphatemia (p<1 mmol/L) in 22 (18%), and hypercalcaemia (Ca >2. 8 mmol/L) in two infants (1.7%). Mean plasma levels of potassium, phosphate and calcium were 1>13±0.18 mmol/L, 0.77±0.17 mmol/L and 2.91±0.017 mmol/L, respectively.

Conclusion Prevalence of hypokalaemia and hypophosphataemia were 93% and 18%, respectively, similar trends as in Bonsante et al’s study. ¹ Therefore, they could be explained by the hypothesis of the anabolic-state-cell. Nevertheless, hypercalcaemia occurred in 1.7% versus 30.2% of infants in Bonsante et al’s group. ¹ Apparently, calcium imbalance was detected earlier and corrected in our cohort.

Close monitoring of the analytical determinations by the pharmacist would allow anticipation and correction of electrolyte imbalances by proposing changes in PN composition.

Reference and/or Acknowledgements 1. Bonsante F, et al. Initial amino acid intake influences phosphorus and calcium homeostasis in preterm infants – it is time to change the composition of the early parenteral nutrition. PLoS ONE2013;8(8):1–9.

No conflict of interest